Bifidobacterium longum product for improving concentration and memory and use thereof

Abstract

The application belongs to the technical field of microorganisms, and particularly relates to a Bifidobacterium longum product for improving concentration and memory and application thereof. The Bifidobacterium longum BB100 has a preservation number of GDMCC No:67126, and the strain can effectively weaken the negative influence of LPS on the accuracy of 5-CRSTT task of mice, not only has a relieving effect on LPS-induced systemic inflammatory response of mice, but also can improve the antioxidant level of mice. It is found through RT-qPCR detection that the strain can repair the intestinal barrier and maintain the intestinal homeostasis by up-regulating the expression of intestinal barrier genes, and can greatly improve the expression of neurotransmitter metabolism related pathway genes to maintain the nervous system homeostasis and regulate the body movement function. Therefore, the Bifidobacterium longum BB100 can realize the regulation of the body concentration by relieving the body inflammation, regulating the oxidative stress state and affecting the expression of neurotransmitters.

Description

Technical Field

[0001] This invention belongs to the field of microbial technology, specifically relating to products and applications that use Bifidobacterium longum to improve concentration and memory. Background Technology

[0002] Attention, as a core cognitive function supporting high-level cognitive activities, is valued for its ability to accurately filter distracting information from the environment, efficiently select target information, and significantly optimize individual behavior. From the perspective of daily behavioral regulation, achieving clear understanding of things, making accurate responses, and maintaining controllability and orderliness all heavily rely on a good level of attention. However, attention deficit has become a significant problem affecting health and quality of life. Mild attention deficit can lead to decreased efficiency and increased errors in learning and work, making it difficult to complete complex tasks; severe attention deficit can severely weaken self-care abilities and even prevent individuals from independently meeting basic daily needs, placing a heavy burden on individuals, families, and society. More importantly, attention deficit often exists in isolation, frequently accompanied by hyperactivity, impulsivity, and other behavioral symptoms, further exacerbating the damage to an individual's physical and mental functions.

[0003] In the search for interventions to improve attention deficit and related health problems, probiotics, as a class of live microorganisms with clear health benefits for the host, have gradually become a research hotspot. Probiotics colonize the host's gut and can prevent and assist in the treatment of diseases by producing beneficial metabolites such as short-chain fatty acids and vitamins, or by regulating the composition and structure of the host's gut microbiota. Among them, *Bifidobacterium longum*, as a key member of the human gut microbiota, occupies an important position in the gut micro-ecosystem, especially in the intestines of infants, where it is one of the most abundant microbial species. Further research has found that *Bifidobacterium longum* is distributed in the intestines of people of different ages. For example, *Bifidobacterium breve* and *Bifidobacterium longum* subspecies *infant* are commonly found in the intestines of breastfed infants. In the adult gut, although the abundance of *Bifidobacterium adolescentis* and *Bifidobacterium streptavidin* is relatively increased, *Bifidobacterium longum* can still exist stably. This broad host adaptability lays the foundation for its development and application as a probiotic strain.

[0004] The probiotic functions of *Bifidobacterium longum* are diverse and extensive. These functions largely depend on bioactive substances that interact with the host (such as bacteriocins and extracellular polysaccharides) and surface-related molecules (such as adhesion proteins and lipoteichoic acid). Numerous preclinical and clinical studies have fully demonstrated the probiotic efficacy of *Bifidobacterium longum*, highlighting its positive role in various aspects, including digestive health (such as improving intestinal barrier function and alleviating irritable bowel syndrome symptoms), regulation of nervous system function, prevention of respiratory infections, maintenance of immune system balance, cardiovascular protection, improvement of metabolic disorders, and regulation of skin homeostasis.

[0005] Currently, clinical interventions for attention deficit disorder are mainly based on drug treatment. However, some drugs have significant side effects and poor long-term tolerance. There is an urgent need to develop safe, effective, and low-side-effect non-drug interventions. Bifidobacterium longum, with its good safety profile, is undoubtedly one of the ideal candidates. However, the efficacy and specificity of existing strains still cannot meet the diverse clinical needs.

[0006] In conclusion, given the serious harm that attention deficit causes to individual health and quality of life, the close relationship between related mental illnesses and attention disorders, and the research gaps and functional limitations of existing Bifidobacterium longum strains in the intervention of attention deficit, it is urgent to develop new Bifidobacterium longum strains. Summary of the Invention

[0007] To address the aforementioned shortcomings, this invention provides a novel Bifidobacterium longum strain and its applications. This strain can fill the gap in the field of probiotics in attention regulation by regulating the body's oxidative balance (restoring brain CAT and NO levels), alleviating inflammatory responses (reducing inflammatory factors such as IL-6), activating the BDNF metabolic pathway (enhancing the expression of key genes and restoring 5-HT levels to improve concentration), and repairing the intestinal barrier (increasing occludin-1 expression). It provides a safe and efficient non-drug intervention solution for attention deficit and related mental illnesses.

[0008] The technical solution of this invention is as follows: On the one hand, the present invention provides the application of a strain of Bifidobacterium longum BB100 in the preparation of products that improve concentration, wherein the preservation number of Bifidobacterium longum BB100 is GDMCC No: 67126.

[0009] Specifically, the product in question is a medicine.

[0010] More specifically, the drug is the fermentation broth, fermentation broth supernatant, fermentation broth precipitate, lyophilized powder and / or bacterial suspension of Bifidobacterium longum BB100.

[0011] The fermentation broth refers to the liquid obtained by inoculating the microbial strain into a culture medium and culturing it for a period of time.

[0012] Preferably, the supernatant of the fermentation broth refers to the clear liquid at the top after centrifugation of the fermentation broth; it contains abundant metabolic products from the bacterial growth and reproduction process and some bacterial fragments. The acidic substances and bacteriocins secreted by the bacteria have antagonistic and killing effects on harmful bacteria. The amino acids and vitamins synthesized by the bacteria after decomposing food are also in the culture medium, as well as enzymes secreted by the bacteria that are useful to the human body. Some of the bacterial components also have an immune-boosting effect on the human body.

[0013] Preferably, the fermentation broth precipitate refers to the liquid precipitate obtained by centrifugation, which includes free protein, residual bacterial cells, broken cells, and culture medium residue, mainly protein and intracellular matrix.

[0014] Preferably, the lyophilized powder is obtained by lyophilizing the culture medium; the lyophilized powder generally also includes a lyophilization protectant. The lyophilization protectant includes, but is not limited to: pH buffers, fillers, sugars, nonionic surfactants, ligands, etc. The pH buffers include, but are not limited to, any one or more of Tris, amino acids or their salts, citric acid or its salts, acetic acid or its salts. The fillers include, but are not limited to, any one or more of mannitol, glycine, and bovine serum albumin. The sugars can be disaccharides, such as sucrose or trehalose, any one or more. The nonionic surfactants include, but are not limited to, Tween, and Tween can be selected from Tween-20, Tween-60, Tween-80, etc. The lyophilization protectant may also include antioxidants, etc. Specifically, the lyophilization protectant may also include albumin, polyethylene glycol, etc.

[0015] Preferably, the bacterial suspension is a homogeneous suspension formed by discarding the supernatant after centrifuging the culture medium, adding water, culture medium or buffer solution, and shaking or blowing to suspend the lower layer of bacteria.

[0016] Specifically, the drug also includes pharmaceutically acceptable excipients.

[0017] More specifically, the pharmaceutically acceptable excipient is selected from at least one of fillers, binders, disintegrants, lubricants, flavoring agents, preservatives, suspending agents, and solubilizers.

[0018] Preferably, the filler is selected from one or more of lactose, sucrose, mannitol, and microcrystalline cellulose; the binder is selected from one or more of hydroxypropyl methylcellulose, povidone, and starch paste; the disintegrant is selected from one or more of crospovidone, sodium carboxymethyl starch, and low-substituted hydroxypropyl cellulose; the lubricant is selected from one or more of magnesium stearate, talc, and silica; the flavoring agent is selected from one or more of steviol glycosides, sucralose, and lemon flavoring; the preservative is selected from one or more of potassium sorbate, sodium benzoate, and parabens; the suspending agent is selected from one or more of xanthan gum, gum arabic, and sodium carboxymethyl cellulose; and the solubilizer is selected from one or more of polysorbate 80, polyethylene glycol 400, and Tween 60.

[0019] Specifically, the dosage form of the drug is a solid dosage form or a liquid dosage form.

[0020] Preferably, the solid dosage form includes, but is not limited to, capsules, tablets, granules or powders; the liquid dosage form includes, but is not limited to, suspensions or emulsions.

[0021] Specifically, the viable count of Bifidobacterium longum BB100 in the drug is not less than 1×10⁻⁶. 7 CFU / g.

[0022] Preferably, the viable count of Bifidobacterium longum BB100 in the drug is not less than 1×10⁻⁶. 9 CFU / g.

[0023] The beneficial effects of this invention are as follows: (1) In this invention, the brain CAT and NO levels of mice treated with Bifidobacterium longum BB100 were not significantly different from those of the normal group, indicating that this strain can regulate the abnormal oxidation level of the body induced by LPS.

[0024] (2) In this invention, the levels of IL-6, IL-1β, IFN-γ, and IL-10 in the model group were significantly higher than those in the normal group. p <0.01), the levels of some inflammatory factors after treatment with Bifidobacterium longum BB100 were still higher than those in the normal group, but significantly lower than those in the model group ( p <0.01) indicates that LPS treatment increases the level of inflammatory factors in mice, which may lead to inflammation and affect normal physiological and biochemical states. However, intervention with Bifidobacterium longum BB100 can slow down the rise in the level of inflammatory factors and alleviate the inflammatory response in the body.

[0025] (3) The results of this invention indicate that LPS treatment leads to significantly lower relative expression levels of key genes BDNF and ERK1 / 2 in the BDNF metabolic pathway in the mouse brain compared to the normal group. p<0.01), after treatment with Bifidobacterium longum BB100, the relative expression levels of the three key genes were significantly increased, all of which were extremely significantly higher than those in the model group ( p <0.01). Changes in the accuracy of the 5-CRSTT training task also illustrate the regulatory effect of Bifidobacterium longum on the body's attention. Measurements of the BDNF gene expression pathway and detection of 5-HT levels in brain tissue demonstrate that Bifidobacterium longum can alleviate the decrease in neurotransmitter expression caused by LPS, maintain the homeostasis of the nervous system, and thus regulate the body's attention and cognitive imbalance.

[0026] (4) In this invention, the relative mRNA expression levels of occludin-1 in the model group were significantly lower than those in the normal group. p <0.05, the relative expression level of occludin-1 mRNA in the cecum of mice in the bacterial culture treatment group was significantly higher than that in the model group ( p The value <0.01 indicates that treatment with Bifidobacterium longum BB100 can alleviate the damage to the intestinal barrier caused by LPS in mice and restore some normal physiological functions of the body.

[0027] Preservation instructions: Biomaterials: Bifidobacterium longum BB100; Category Naming: Bifidobacterium longum ; Accession number: GDMCC No: 67126; Preservation period: October 17, 2025; Preservation institution: Guangdong Provincial Center for Microbial Culture Collection; Abbreviation of depositary institution: GDMCC; Address: 5th Floor, Building 59, No. 100 Xianlie Middle Road, Guangzhou. Attached Figure Description

[0028] Figure 1 The changes in organ indices in mouse brain tissue are shown. The same letter indicates no significant difference, and different letters indicate significant differences. p <0.01, A is the brain organ coefficient (brain organ index), and B is the liver organ coefficient (liver organ index).

[0029] Figure 2 The results show the morphological observation of mouse brain tissue.

[0030] Figure 3 The accuracy rate of the 5-CRSTT training task in mice.

[0031] Figure 4 The graph shows the changes in 5-HT levels in mouse brain tissue. The same letter indicates no significant difference, while different letters indicate significant differences. p <0.01.

[0032] Figure 5 The graph shows changes in oxidative stress levels in mice. The same letter indicates no significant difference, while different letters indicate significant differences. p <0.01, A is brain tissue GSH, B is brain tissue CAT, C is brain tissue NO.

[0033] Figure 6 The change in serum inflammation levels in mice is represented by the same letter, indicating no significant difference, while different letters indicate a significant difference. p <0.01, A is serum IL-6, B is serum IL-10, C is serum IFN-γ, D is serum IL-1β.

[0034] Figure 7 The graph shows the relative expression levels of genes in the BDNF metabolic pathway in the mouse brain. The same letter indicates no significant difference, while different letters indicate significant differences. p <0.01, A is BDNF The relative expression level of genes, B is ERK1 / 2 The relative expression level of genes, C is CREB The relative expression level of genes.

[0035] Figure 8 The graph shows the relative expression levels of intestinal barrier genes in the mouse cecum. The same letter indicates no significant difference, while different letters indicate significant differences. p <0.01, A represents the relative expression level of the tight junction protein-1 gene, B represents... ZO-1 The relative expression level of the gene, where C is the relative expression level of the closure protein-1 gene. Detailed Implementation

[0036] The present invention will be further clearly and completely illustrated below through embodiments. These embodiments are only some examples of the present invention and are not intended to limit the present invention, but are only for illustrating the present invention. Unless otherwise specified, the experimental methods used in the following embodiments are all conventional experiments, and the materials and reagents used in the following embodiments are commercially available unless otherwise specified.

[0037] The main reagents, instruments and equipment used in this invention are shown in Table 1: Table 1. Main Reagents, Instruments and Equipment

[0038] Example 1 1.1 Experimental Methods 1.1.1 Animal Model Thirty 6-week-old male C57BL mice purchased from Hunan Slack Jingda Experimental Animal Co., Ltd. were randomly divided into 5 groups of 6 mice each: normal control group, model group, HD-BB100 group (high-dose BB100 group: 1×10⁻⁶). 9 CFU / kg of Bifidobacterium longum BB100), LD-BB100 group (low-dose BB100 group: 1×10 7 The treatment regimens were as follows: The normal control group received no treatment; the model group received oral administration of normal saline for 14 days, followed by intraperitoneal injection of sterile LPS solution (0.83 mg / kg) for 3 consecutive days starting from day 10; the baicalin group received oral administration of baicalin (60 mg / kg) for 14 days, followed by intraperitoneal injection of sterile LPS solution for 3 consecutive days starting from day 10; the high-dose BB100 group received oral administration of high-dose bacterial solution for 14 days, followed by intraperitoneal injection of sterile LPS solution for 3 consecutive days starting from day 10; the low-dose BB100 group received oral administration of low-dose bacterial solution for 14 days, followed by intraperitoneal injection of sterile LPS solution (0.83 mg / kg) for 3 consecutive days starting from day 10. The oral and injection doses were both 0.1 mL / 10 g.

[0039] The preparation method of the Bifidobacterium longum BB100 bacterial suspension is as follows: Bifidobacterium longum BB100 was isolated from healthy breast milk, and the strain was stored at -80 degrees Celsius after isolation and identification. The cryopreserved tube of Bifidobacterium longum BB100 strain was taken from -80 degrees Celsius, thawed, and inoculated (200 μL) into MRS liquid medium (8 mL). The culture was incubated at 37 degrees Celsius for 24 hours, then 3% of the inoculum was transferred to MRS liquid medium and cultured for another 18 hours. The Bifidobacterium longum BB100 strain at the bottom was collected by centrifugation (4 degrees Celsius, 4000 rpm, 10 minutes) and resuspended in physiological saline.

[0040] 5-CRSTT training was performed during gavage, and 5-CRSTT was performed after the final intraperitoneal injection. After the experiment, the relative mRNA expression levels of catalase (CAT), reduced glutathione (GSH), vascular endothelial relaxing factor (NO), mouse interleukins (IL-6, IL-1β, IL-10), interferon-gamma (IFN-γ), and serotonin (5-HT) in mouse serum and brain tissue homogenates were measured; the relative mRNA expression levels of the mouse cecal intestinal barrier genes occludin-1, zo-1, and claudin-1 were also measured; and the relative mRNA expression levels of CREB, ERK, and BDNF genes in mouse brain tissue were measured.

[0041] Mouse serum collection: At the end of the gavage test on day 14, mice that had been fasted for 12 hours were anesthetized, their whiskers were trimmed, and their eyeballs were quickly enucleated. Blood was collected in endotoxin-free tubes. After grouping and labeling, serum samples were incubated at 37°C for 30 min, centrifuged at 4°C and 3000 r / min for 10 min, and the supernatant was frozen at -80°C for subsequent testing, avoiding repeated freeze-thaw cycles.

[0042] Collection of mouse organ tissues: After collecting serum, the mice were quickly dissected, and the whole brain, liver, and cecum were removed and rinsed in pre-cooled physiological saline to remove serum and mucous membranes adhering to them. Surface moisture was then quickly blotted dry with filter paper. The whole brain tissue was cut into pieces and divided into three parts. One part was immersed in 20 times its volume of 4% (v / v) paraformaldehyde (prepared in PBS) solution for tissue observation. Another part was added to 9 times its volume of pre-cooled 0.9% physiological saline and rapidly homogenized in an electric homogenizer. It was then centrifuged at 4°C and 8000 rpm for 15 minutes, and the supernatant was frozen at -80°C for ELISA (enzyme-linked immunosorbent assay) kit detection, avoiding repeated freeze-thaw cycles. The third part was flash-frozen in liquid nitrogen in aluminum foil and quickly transferred to sterile 1.5 mL Eppendorf tubes and frozen at -80°C for quantitative ELISA detection. The liver tissue was weighed and frozen at -80°C for subsequent detection. The cecal tissue was wrapped in aluminum foil and flash-frozen in liquid nitrogen, then quickly transferred to sterile 1.5 mL ep tubes and stored at -80°C for quantitative fluorescence detection.

[0043] 1.1.2 Training and testing of mice using 5-CRSTT (1) Water restriction stage After a week of acclimatization, the mice were placed in a restricted water period for eight consecutive days, with water provided at intervals of 4 hours, 3.5 hours, 3 hours, 2.5 hours, 2 hours, 1.5 hours, 1 hour, and 0.5 hours. Their weight was measured at 10:00 AM each day. If the mouse's weight was below 90% of its previous weight, the water restriction was considered to have achieved the desired result. If it was below 80% of its previous weight, the mouse's health should be monitored to prevent dehydration leading to decreased mobility or even death. After the water restriction period ended, behavioral training was initiated, followed by 15 minutes of water replenishment after each daily behavioral training session.

[0044] (2) Adaptive training phase Mice that meet the health criteria enter the adaptation training phase, which consists of four stages. In the first stage, the 5-choice Habituation 1 program is run (10 min). During this stage, mice are free to explore the control box; the screen and light in the control box are not lit, and no sugar water reward is provided. In the second stage, the 5-choice Habituation 2 program is run (30 min, 100 trials). In this stage, the screen lights are not lit, but the light in the food slot is lit. When the mouse touches the light, it receives a liquid reward (2% sucrose). Through repeated touching of the light, the mouse establishes a connection between the light and the sugar water reward. Each round of the experiment ends when the mouse completes 100 trials or the cumulative experimental time reaches 30 min. If the number of times the reward is received is >50, the mouse proceeds to the third stage; otherwise, the second stage is repeated until the target is met.

[0045] The third stage involves 5-choice touch training (30 minutes, 100 trials). Five screens (4cm x 4cm) are randomly lit. When a mouse touches a screen, a light in the control box illuminates. Upon touching a lit light, sugar water is pumped out of the box as a reward. The five screens are then randomly lit again (without interval) to proceed to the next trial. Mice that receive ≥50 rewards proceed to the fourth stage, 5-choice touch training 4 (30 minutes, 100 trials). This stage is essentially the same as the third stage, except that there is a 5-second interval after each reward. When a mouse achieves >50 correct attempts, it enters the training stage.

[0046] 1.1.3 Detection of 5-HT levels, oxidative stress levels, and serum inflammation levels in mouse brain tissue Preserved serum and brain tissue homogenates were collected, and oxidative stress levels were detected using a catalase (CAT), reduced glutathione (GSH), and vascular endothelial relaxing factor (NO) kit. Simultaneously, ELISA kits were used to determine the levels of IL-6, IL-10, IL-1β, and IFN-γ in serum and the level of 5-HT in brain tissue homogenates. The experimental procedures were performed in accordance with the kit instructions.

[0047] 1.1.4 Morphological observation of mouse brain tissue Brain tissue, fixed with fixative, was harvested in coronal fashion at a thickness of 4 mm. It was then dehydrated in gradients using 70%, 80%, 95%, and 100% ethanol, each dehydration cycle lasting 30 min. After dehydration, the tissue was soaked in xylene for 20 min, followed by paraffin embedding for 30 min. The tissue was then cut into 4 μm sections using a microtome. The sections were gently mounted on glass slides, dried in an oven, and stained with hematoxylin and eosin (HE). Histological characteristics were then observed and analyzed under an optical microscope.

[0048] 1.1.5 Detection of the relative expression levels of CREB, ERK1 / 2, BDNF in mouse brain tissue and intestinal barrier genes zo-1, occludin-1, and claudin-1 mRNA in the cecum RNA was extracted from brain and cecal tissues frozen at -80 °C using the Trizol method. After purity testing, the RNA was frozen at -80 °C for later use. A reverse transcription kit was used, and the extracted RNA was reverse transcribed at ice temperature according to the instructions, with cycles of 65 °C (5 min) → 42 °C (60 min) → 70 °C (5 min) → 4 °C (hold) to obtain cDNA from the corresponding tissues. The Hief Master Mix kit was used, and the template cDNA and primers were mixed according to the kit instructions, with the addition of fluorescent dye and high-fidelity enzyme. PCR amplification was performed under 40 cycles of 95 °C for 5 min; 94 °C for 30 s; 60 °C for 40 s; 72 °C for 1 min. Real-time quantitative PCR analysis was performed using β-actin as an internal reference gene. Primer sequences are shown in Table 2. The CT value method (2...) was used for calculation. -ΔΔCT ).

[0049] Table 2 Primers and their sequences used in reverse transcription quantitative polymerase chain reaction (RT-qPCR)

[0050] 1.1.6 Data Processing The data were analyzed using one-way ANOVA based on the Turkey test. A p-value < 0.05 was considered statistically significant. Plotting software was also used to create graphs.

[0051] 1.2 Results and Analysis 1.2.1 Organ coefficient of mouse brain tissue Organ index represents the movement and physiological function of organs under constant conditions and is an important indicator for toxicological evaluation in mice. An elevated organ index may be due to organ congestion and edema, while a low organ index may be due to muscle atrophy or toxic effects on the body. This study calculated the organ index by weighing mouse brain and liver tissues, and the results are as follows: Figure 1 As shown, the brain organ index of the model group mice was significantly higher than that of the normal group ( p <0.01 indicates that LPS treatment caused cerebral congestion and edema in mice, resulting in abnormal conditions that may affect normal physiological functions; treatment with baicalin reduced organ indices, with no significant difference from the normal group, indicating that baicalin can alleviate LPS-induced organ edema in mice; after treatment with Bifidobacterium longum BB100, the brain organ indices were significantly lower than those in the model group ( p <0.01), and the brain organ index of the high-dose BB100 group was not significantly different from that of the normal group, indicating that Bifidobacterium longum BB100 helps regulate LPS-induced brain congestion and edema in mice and restore normal physiological function. The liver is an important metabolic organ in the body. Studies on liver organ indices in various groups of mice are as follows: Figure 1 As shown in B in the figure, the liver organ index of mice exhibits a similar trend to that of the brain organ index, and the liver organ index of the model group is significantly higher than that of the normal group. p <0.01), after treatment with high doses of Bifidobacterium longum BB100, the organ index of liver tissue was significantly lower than that of the model group ( p The value was <0.01, and there was no significant difference compared to the normal group. This indicates that Bifidobacterium longum BB100 has a probiotic effect in relieving tissue edema and restoring normal physiological functions.

[0052] 1.2.2 Pathological observation of mouse brain tissue like Figure 2 As shown, the normal group's brain tissue structure was intact, with densely packed cells. Multiple inflammatory lesions were observed on the surface of the model group's brain, and the gaps between neurons near the lesions and surrounding tissues increased, indicating that LPS caused edema in the brain tissue. Overall, the model group's brain tissue showed dense staining of nerve cells and indistinct nuclei, indicating that LPS caused cellular shrinkage in the brain tissue, affecting its normal physiological morphology. In the bacterial culture-treated group, some neurons in the cerebral cortex of mice showed degeneration, but no obvious inflammatory cell infiltration was observed; in the low-dose BB100 group, a large number of neurons showed edema, cell swelling, and vacuolated cytoplasm. Therefore, it is evident that Bifidobacterium longum BB100 has a certain protective effect against LPS-induced brain tissue in mice.

[0053] 1.2.3 Changes in the 5-CRSTT index in mice Mice in each group were trained on the 5-CRSTT task. The task accuracy of the mice within the same time period (15 min) was as follows: Figure 3 As shown in the figure, after LPS gavage modeling, the task accuracy of mice in the model group decreased by 74.71%, and the other treatment groups also showed a decrease. The task accuracy of mice in the baicalensis glycoside group decreased by 52.77%, which was a slight improvement compared to the model group. The task accuracy of mice in the high-dose BB100 group decreased by 64.93%, which was also a slight improvement compared to the model group. The task accuracy of mice in the low-dose BB100 group decreased by 79.25%, indicating that Bifidobacterium longum BB100 can improve LPS-induced cognitive imbalance. Moreover, overall, the improvement effect of the high-dose BB100 group was more significant.

[0054] 1.2.4 Changes in 5-HT levels in mouse brain tissue The levels of 5-HT in the brain tissue of mice in each group were as follows: Figure 4 As shown in the figure, LPS treatment resulted in a significantly lower level of 5-HT in the mouse brain compared to the normal group. p The value <0.01 indicates that LPS leads to serotonin accumulation in the brain, causing neurotransmitter imbalance and affecting normal physiological functions. After treatment with Bifidobacterium longum BB100, the 5-HT level in the brain tissue decreased to some extent; the 5-HT level in the brain tissue of mice in the high-dose BB100 group was significantly lower than that in the model group. p The concentration of 5-HT in the brain tissue of mice was <0.05, and there was no significant difference compared with that in the scutellaria baicalensis group, indicating that high doses of Bifidobacterium longum BB100 can regulate LPS-induced neurotransmitter imbalance.

[0055] 1.2.5 Changes in oxidative stress levels in mice The levels of GSH, CAT, and NO in the brain tissue of mice in each group are as follows: Figure 5 As shown in the figure, LPS treatment resulted in significantly lower levels of CAT and NO in the mouse brain compared to the normal group. p The value <0.01 indicates that LPS can cause oxidative stress in the body, affecting normal physiological functions. After treatment with Bifidobacterium longum BB100, the level of oxidative stress in the body changed to some extent, and was significantly higher than that in the model group. Moreover, the CAT and NO levels in the high-dose BB100 group were not significantly different from those in the normal group.

[0056] 1.2.6 Changes in serum inflammation levels in mice Serum inflammation levels in each group of mice were as follows: Figure 6 As shown in the figure, LPS treatment resulted in significantly higher levels of IL-6, IL-10, IFN-γ, and IL-1β in the mouse brain compared to the normal group. pThe value <0.01 indicates that LPS significantly increases the level of inflammatory factors in the body, thereby triggering an inflammatory response and affecting normal physiological functions. After treatment with Bifidobacterium longum BB100, the level of inflammatory factors in the body was downregulated and lower than that in the model group. Furthermore, overall, the high-dose BB100 group showed a more significant regulatory effect on reducing inflammation levels.

[0057] 1.2.7 Changes in the relative expression levels of genes in the BDNF metabolic pathway in the mouse brain Changes in the relative expression levels of BDNF metabolic pathway genes in the brains of mice in each group are as follows: Figure 7 As shown in the figure, LPS treatment leads to the degradation of key genes in the BDNF metabolic pathway in the mouse brain. BDNF and ERK1 / 2 The relative expression levels of both groups were significantly lower than those of the normal group. p <0.01 indicates that LPS leads to a decrease in the expression of genes related to the BDNF metabolic pathway in the brain, resulting in neurotransmitter imbalance and affecting the maintenance of normal nervous system function in mice. After treatment with Bifidobacterium longum BB100, the relative expression levels of the three key genes were significantly increased, all of which were significantly higher than those in the model group ( p <0.01). Furthermore, overall, the high-dose BB100 group had a more significant effect on the expression of the BDNF metabolic pathway in the mouse brain.

[0058] 1.2.8 Changes in the relative expression levels of intestinal barrier genes in the mouse cecum The changes in the relative expression levels of intestinal barrier genes in the cecum of mice in each group are as follows: Figure 8 As shown in the figure, LPS treatment downregulates the expression of intestinal barrier genes in the mouse cecum, disrupting the intestinal barrier and leading to physiological imbalance. After treatment with Bifidobacterium longum BB100, the relative expression levels of the three barrier gene mRNAs were significantly increased, all significantly higher than those in the model group ( p The result was <0.05, indicating that Bifidobacterium longum BB100 can alleviate the damaging effect of LPS on the intestinal barrier, and overall, the protective effect of the high-dose BB100 group was more significant.

[0059] This invention employs a mouse model of attention deficit induced by gavage administration of LPS solution combined with 5-CRSTT training. LPS affects the levels of inflammation and oxidative stress in the body, causing neurotransmitter imbalance and leading to attention deficit in mice. Experimental results show that *Bifidobacterium longum* BB100 can effectively attenuate the effect of LPS on the accuracy of the 5-CRSTT task in mice, and also has a certain alleviating effect on LPS-induced systemic inflammatory response in mice, reducing the levels of inflammatory factors IL-6, IL-1β, IFN-γ, and IL-10. It can also increase the antioxidant levels in mice and accelerate the consumption of CAT and NO. RT-qPCR detection revealed that this strain can repair the intestinal barrier by increasing the expression of intestinal barrier genes, maintaining intestinal homeostasis, thereby maintaining normal physiological functions; simultaneously, it can significantly increase the expression of genes related to neurotransmitter metabolism pathways, maintaining nervous system homeostasis, thereby regulating the body's motor function.

[0060] In summary, Bifidobacterium longum BB100 can alleviate inflammation, regulate oxidative stress, and improve concentration by influencing neurotransmitter expression.

[0061] The above detailed description is a specific illustration of one feasible embodiment of the present invention, and this embodiment is not intended to limit the patent scope of the present invention. It should be noted that all equivalent implementations or modifications made without departing from the present invention should be included within the scope of the technical solution of the present invention. Therefore, the protection scope of the present invention should be determined by the appended claims.

Claims

1. Bifidobacterium longum ( Bifidobacterium longum The application of BB100 in the preparation of products that improve attention deficit, characterized in that, The preservation number of the Bifidobacterium longum BB100 is GDMCC No: 67126; The application described therein involves alleviating inflammation and regulating the body's oxidative stress state, which can then affect the expression of neurotransmitters and thus regulate the body's concentration.

2. The application according to claim 1, characterized in that, The product in question is a medicine.

3. The application according to claim 2, characterized in that, The drug is a fermentation broth precipitate, lyophilized powder, and / or bacterial suspension of Bifidobacterium longum BB100.

4. The application according to claim 2, characterized in that, The drug also includes pharmaceutically acceptable excipients.

5. The application according to claim 4, characterized in that, The pharmaceutically acceptable excipients are selected from at least one of fillers, binders, disintegrants, lubricants, flavoring agents, preservatives, suspending agents, and solubilizers.

6. The application according to claim 5, characterized in that, The filler is selected from one or more of lactose, sucrose, mannitol, and microcrystalline cellulose; the binder is selected from one or more of hydroxypropyl methylcellulose, povidone, and starch paste; the disintegrant is selected from one or more of crospovidone, sodium carboxymethyl starch, and low-substituted hydroxypropyl cellulose; the lubricant is selected from one or more of magnesium stearate, talc, and silica; the flavoring agent is selected from one or more of steviol glycosides, sucralose, and lemon flavor; the preservative is selected from one or more of potassium sorbate, sodium benzoate, and parabens; the suspending agent is selected from one or more of xanthan gum, gum arabic, and sodium carboxymethyl cellulose; and the solubilizer is selected from one or more of polysorbate 80, polyethylene glycol 400, and Tween 60.

7. The application according to claim 2, characterized in that, The drug is in the form of a solid dosage form or a liquid dosage form.

8. The application according to claim 7, characterized in that, The solid dosage forms include capsules, tablets, granules, or powders; the liquid dosage forms include suspensions or emulsions.

9. The application according to claim 2, characterized in that, The viable count of Bifidobacterium longum BB100 in the drug is not less than 1×10⁻⁶. 7 CFU / g.

10. The application according to claim 2, characterized in that, The viable count of Bifidobacterium longum BB100 in the drug is not less than 1×10⁻⁶. 9 CFU / g.

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